The DataCenter I commented on was using, as mentioned, LT03 level tapes for backing up about 3 terabutes of data nightly either full in some cases or differential in others. Backup time was 15 hours end to end.

Tape has about a 47% failure rate and restoration at 2 in the morning is not the time to discover that tape 3 is bad.

A municipality, in PROCESSOR magazine, changed from a like scenario to a hard drive based format which cut backup time to 5 hours and also provides (a) certainty of restoration at a (b) higher speed as well.

Secondly, nobody really tests. And that makes it all worthless. I test for my small business clients and have better DR plans for their offices than the DataCenter EVER could have. Yes it is smaller and such, but a small business has ONE location anyway so the impact of loss is, well, TOTAL. DataCenters tend to be linked to other servers where a modicum of corporate support will still reside in any situation.